i phase -> 3 phase ?

[Jim Hawkins]

Are there any solid-state devices to convert 240 v 1 phase to 415 volt
3-phase ? Available in the UK ?
I would like to run a small (1/8 hp) 415 volt 3 phase motor from
the 240 volt single phase supply.

Jim Hawkins

 

[John Popelish]

Are there any solid-state devices to convert 240 v 1 phase to 415 volt
3-phase ? Available in the UK ?
I would like to run a small (1/8 hp) 415 volt 3 phase motor from
the 240 volt single phase supply.

A variable frequency drive rectifies the single (or 3 phase)
line power into DC, then constructs 3 phases of AC from the
DC supply, usually with a PWM modulation method. But this
produces an AC output voltage about as high as the AC input
voltage, so if you cannot reconnect the motor for lower
voltage operation, you would need a 3 phase step up
transformer between the drive an the motor, also.

Here is an example of this kind of drive:
http://web2.automationdirect.com/adc/Shopping/Catalog/AC_Drives/GS1_(120_-z-_230_VAC_V-z-Hz_Control)

 

[[email protected]]

Are there any solid-state devices to convert 240 v 1 phase to 415 volt
3-phase ? Available in the UK ?
I would like to run a small (1/8 hp) 415 volt 3 phase motor from
the 240 volt single phase supply.

Jim Hawkins

A variable frequency drive (VFD) such as
http://www.joliettech.com/abb_acs350_general_machinery_drives-technical_specifications.htm

-Lasse

 

[WJLServo]

Are there any solid-state devices to convert 240 v 1 phase to 415 volt
3-phase ? Available in the UK ?
I would like to run a small (1/8 hp) 415 volt 3 phase motor from
the 240 volt single phase supply.

Jim Hawkins

Real "old school" way to do this would be to use a transformer to step
up to 415 volts, and then a good sized "starting" capacitor to do a
fairly bad job of synthesizing phase lag to power 3rd phase lead on
motor. Efficiency isn't nearly so good as with modern solid state
drives, but, it's cheap, and you see lots of old machine tools and
other gear with 3 phase induction motors run that way, hooked to
single or two phase mains....

W Letendre

 

[[email protected]]

A variable frequency drive rectifies the single (or 3 phase)
line power into DC, then constructs 3 phases of AC from the
DC supply, usually with a PWM modulation method. But this
produces an AC output voltage about as high as the AC input
voltage, so if you cannot reconnect the motor for lower
voltage operation, you would need a 3 phase step up
transformer between the drive an the motor, also.

Here is an example of this kind of drive:http://web2.automationdirect.com/adc/Shopping/Catalog/AC_Drives/GS1_(...)

assuming it is "normal" european 3-phase the 415V is between phases,
each phase to neutral is still only 240, so not step up should be
needed

-Lasse

 

[Jim Hawkins]

I know you asked for solid state but rotary is cheap:

1.5kW for £490 from www.isomatic.co.uk


The good thing about rotary converters is that they are *much* more
tolerant of short term overload.

Michael Kellett

Bit overkill for 1/8 hp though !
I've just found this on eBay:-
http://cgi.ebay.co.uk/NEW-3-4HP-240...hZ010QQcategoryZ42899QQtcZphotoQQcmdZViewItem

3/4hp and only £125 or so.

Thanks to all for your information and interest.

Jim Hawkins